Technical Abstract:
There has been a lot of recent interest in using agricultural products as raw materials to produce functional polymers. The motivation is to add value to agricultural products and to decrease the global dependence on petroleum-based feedstock. Moreover, agricultural materials are renewable, biodegradable, and sustainable. NMR is an excellent tool to characterize agricultural products, to monitor reactions, to elucidate reaction mechanisms, and to relate the polymer structures to end-use properties. Several examples where NMR has played an important role in new product development will be shown in this work. These include the production of cellulosic derivatives from agricultural residues and the modifications of triglyceride oils using nitrogen-containing reagents. In all these cases, NMR has been used successfully to decipher the product structures and reaction mechanisms. Another example is the derivatization of zein, the main storage protein in corn. (The 1H NMR spectrum of the zein-MDI product is shown in the attached figure.) The use of NMR on the reactions of isocyanates with zein in solution has permitted major reaction pathways to be identified. As a result of the modification reactions, the zein derivatives exhibit improved properties.